1. Field of Invention
This invention relates to an abrading tool, and more particularly, to a continuous loop sanding belt tool being a block having two sections adapted for mounting and removing a continuous sanding belt wherein the two sections are slidable interconnected with a resilient member adapted to push the two sections apart.
2. Related Art
Smoothing and abrading metal and wood surfaces can be accomplished by sanding the surface with an abrasive material such as sandpaper. Sanding can be done either mechanically with a power sander or manually by hand. Manual sanding is made easier and more efficient by using a sanding block in conjunction with a strip or sheet of sanding paper. A sanding block can be anything from a rectangular section of wood, such as a 2×4, to which the sandpaper is secured, to a specially configured block having a curved resilient surface which receives the sandpaper and includes fastening means at the ends of the block for securing the sandpaper to the surface.
In addition to strips or sheets of sanding paper, there also are sanding belt tools having a continuous loop or belt of sanding paper used in conjunction with a tension mounted block for manual sanding. A tension mounted block used in a sanding belt tool typically comprise a pair of blocks with like cross sections which may be of equal or unequal lengths and disposed in coplanar relationship to one another. The two blocks are held in spaced relationship by one or more relatively strong springs. In operation, the blocks are pressed together, thereby compressing the springs, so that the sanding belt is positioned around the blocks. Once in place, the holding pressure on the blocks is released so that the blocks move apart to provide tension to the sanding belt, thereby holding the sanding belt in place around the blocks. This type of tension mounted block usually includes one or more dowel pins on one block that are slidably and removably inserted in corresponding spring locked sockets of the other block. Thus, with this type of tension mounted block, the two blocks are manually pressed or wedged together while at the same time the user must handle the sanding belt for mounting or removal. Since the two blocks are freely movable relative to each other only to a point which will exert the appropriate amount of pressure on the continuous belt surrounding it, any loss of the manual grip on the pressed together blocks before the sanding belt is adequately in place will result in the blocks moving away from each other under the force of the springs—even to the point of complete separation.
One attempt to overcome this separation problem involves a hand sanding block formed from two blocks which are freely movable towards and away from each other, but not to the point of separation. For example, in U.S. Pat. No. 5,383,308 to Beloff, et al., the two blocks are positioned by a pair of spaced dowel pins with springs attached and projecting from one block for telescopic engagement into a corresponding hole of the other component block wherein the two blocks are held apart in spaced relationship by screw secured springs traversely inserted into the end of spiral of the springs. That is, the screws are inserted through the top surface of the sanding block and into the springs to prevent the springs from exiting the block into which they are inserted, thereby preventing the blocks from separating. For mounting and removing the continuous belt, the blocks are pressed together so that the inner ends of the blocks abut. Once the sanding belt is in place around the blocks, the holding pressure is released and the blocks move apart to provide tension on the sanding belt.
While this arrangement, i.e., the screws inserted into the springs, does prevent the blocks from inadvertently separating completely from each other, it is still difficult to mount and remove the continuous sanding belt because the springs must be manually compressed while at the same time manipulating the sanding belt onto the sanding block. Thus, there remains a need in the art for a simple means of mechanically holding the blocks in a compressed position thereby enabling a user to freely mount or remove the continuous sanding belt from around the blocks while eliminating the possibility of the user inadvertently releasing the pressure on the blocks and causing the blocks to separate.